Some of the more common adverse events that occur during ENT and oral surgery resulting from the use of electrosurgical units (ESUs) and powered or manual instrumentation include: (1) inadvertent burns to the lips and specifically the oral commissure; (2) inadvertent damage to the lips with powered or manual instrumentation; (3) airway fire; and (4) potentially hazardous smoke plume in the surgical environment.
Lip burns may be caused in several ways. For example the surgeon may touch an activated electrosurgical device to a metal instrument (such as an Allis clamp, forceps, or Hurd retractor) that is resting upon the oral commissure, thus sending energy up the instrument to the lip at the point of contact. Lip burns may also happen when the surgeon fails to deactivate the electrosurgical device as it is removed from the mouth, resulting in the electrode inadvertently contacting the patient's lip upon exit. Also, any malfunction that would cause insulation on the shaft of the electrosurgical device to melt around the area of the lips may cause lip burns. Damage to the lips may also occur during inadvertent contact with powered instrumentation such as drills and burs during oral and trans oral surgery. A number of methods may be employed to mitigate damage to the lips including insertion of dental cheek and lip retractors commonly for teeth whitening, draping of wet gauze over the lips and oral commissure, and use of the surgeon's gloved fingers as an insulator between ESUs, metal instruments, and the patient's lips. However, each of these methods presents one or more drawbacks, as discussed below.
Airway fires may occur when there is an ignition source, an oxidizer, and fuel present. Electrosurgical units (ESUs) may provide the ignition source, and during otolaryngology (ENT) surgeries, such as a tonsillectomy, the oral cavity may allow the collection of gases and an oxygen-enriched atmosphere (OEA). This gas or smoke may also collect as many ENT surgeons chose to operate with a paddle or needle tip electrocautery device that does not have integrated suction to remove accumulating gases and smoke. An additional surgical staff member may often hold a suction tip at the edge of the mouth to evacuate smoke and leaking gases. However, if this assistant loses attention or improperly holds the suction, gases may collect in the oral cavity, increasing fire risk. Likewise, if the patient is suspended via a mayo stand, the surgical staff member responsible for suction gas and smoke has been found to have a tendency to grow tired during the procedure and lean on the mayo stand, thus increasing the risk of dislocating the patient's jaws. Fine-dissecting electrosurgical tips with integrated suction are now available, yet they are rarely used as surgeons prefer the unencumbered feel of a device without suction tubing attached.
Studies have also shown that smoke plume resulting from electrosurgical devices may be a carcinogen, a mutagen, and an infectious vector capable of causing harm to the surgical staff. Literature suggests that surgical smoke is comprised of over 150 chemicals, including benzene, hydrogen cyanide, toluene, perchloroethylene, formaldehyde, acrylonitrile, and ethylbenzene. One study suggests that one day of surgical smoke exposure in an operating theatre is equal to the carcinogen effects of 27 cigarettes. HPV, HIV, and hepatitis pathogens capable of transmitting disease have also been found in surgical smoke plume. Again, the surgical assistant holding a suction device is the most widely used solution to remove these potentially hazardous electrosurgical by-products, with similar potential disadvantages to those discussed above. Gas and surgical smoke plume evacuation may be particularly challenging during TransOral Robotic Surgery (TORS).
Oral retractors in use today, such as the dental lip and cheek retractors commonly used for teeth whitening procedures, do not provide the unique requirements for an ENT or oral surgeon, as they are predominantly designed for visual access to the teeth only in a closed-jaw position. ENT, oral and maxillofacial surgeons more often require easy access to the oral cavity, nasopharnyx, oropharynx, and laryngopharnyx; adequate burn and damage protection of the lips and oral commissure from either electrosurgical devices or powered instrumentation; design allowance for the mouth gag/retractor (i.e., Crowe-Davis, McIvor, Whitehead, Molt, Denhart, Roser-Koenig, Fergusson-Ackland, Jennings, Kilner-Doughty, Davis-Boyle, Dingmann, FK-WO TORS, etc.) and airway tube; design allowance for elongated geometry of oral cavity during mouth gag suspension; construction from a non-flammable, heat-resistant material; and a need to keep the surgical site clear of obstructions such as suction tubing, etc., that may inhibit a surgeon's view or movement, and a need to evacuate smoke/gas.
Headlights utilized for standard illumination of the oral cavity are expensive, cumbersome, and can present hazards in the operating suite due to the tethering of the light source to the surgeon and potential fire risks. In academic teaching institutions, resident and attending surgeons often share one head light during surgery, compromising the sterile field. In emergency situations, such as a post-operative tonsillectomy hemorrhage, peritonsillar abscess, or foreign body admitted to an Emergency Department, proper illumination can be difficult to achieve, resulting in compromised patient safety. Overseas and low income medical work is often hindered by lack of access to proper lighting as well, impacting the level of care traveling oropharyngeal surgeons can provide to patients.
Visual access to the oral cavity is limited, especially in teaching situations where a surgical resident, medical student, attending surgeon, or other observer must look over the shoulder of the operating surgeon to visualize the procedure as it unfolds. Various retractors have been utilized to spread the lips and cheeks laterally to improve visual access with limited success.
Postoperative hemorrhage is one of the primary concerns of tonsil surgeons, and has been for over 3,000 years. Numerous methods have been devised to locate and seal blood vessels intraoperatively. However, no single technique has stood out in solving the problem of postoperative hemorrhage and identification of blood vessels at or near the surface of the surgical area is problematic. Post-op bleeds requiring surgical intervention still occur after 5 percent of all tonsillectomies.